1. Technical Field
The present invention relates to a package base, a package, an electronic device including this package, and an electronic apparatus and a moving object including this electronic device.
2. Related Art
As a technique concerning bonding of a ceramic substrate relevant to a package base serving as a main body part of a package which is a constituent element of an electronic device and houses an electronic component, there has been known a production method, in which a bonding paste containing an active metal-containing brazing filler metal is applied onto a ceramic substrate, the ceramic substrate and a metal plate are placed in a stacked manner, and thereafter, both members are bonded to each other by a heat treatment, and then, an unnecessary portion of the metal plate is removed by an etching treatment, whereby a ceramic wiring board having a desired wiring pattern is obtained (see, for example, JP-A-8-46325).
In the ceramic wiring board produced by the above production method, as the bonding paste containing an active metal-containing brazing filler metal, specifically, a bonding paste containing a Ti—Ag—Cu alloy obtained by blending Ti (titanium) which is an active metal in a metal having an Ag (silver)-Cu (copper) eutectic composition is used.
It is believed that according to this, in the ceramic wiring board, the bonding strength between the ceramic substrate and a metal plate is improved, and thus, excellent thermal shock resistance and high reliability are obtained.
When the above bonding paste is applied to, for example, a package (container) to be used for an electronic device or the like, it is necessary to bond a ceramic substrate (corresponding to a package base) and a metal plate (corresponding to a lid) to each other with a gap in the thickness direction through the bonding paste applied in a frame shape in plan view and to form an internal space for housing an electronic component or the like between the ceramic substrate and the metal plate.
However, the above bonding paste has relatively high fluidity, and therefore has a problem that it easily spreads to the periphery even if it is applied in a predetermined shape, and lacks a shape retention property for retaining the predetermined shape (in other words, the ratio of the height relative to the application width is small).
As a result, in the case of a package using the above bonding paste, in order to ensure the height of the internal space, when the bonding paste is applied, a reasonable application space including a space where the paste may spread is needed, and therefore, it may be difficult to further reduce the size.